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8. Spectroscopic Characterization of Impactites and a Machine Learning Approach to Determine the Oxidation State of Iron in Glass‐Bearing Materials.

Author

Bruschini, E., Carli, C., Skogby, H., Andreozzi, G. B., Stojic, A., and Morlok, A.

Subjects
IRON oxidation, MACHINE learning, OXIDATION states, SPECTRAL reflectance, X-ray powder diffraction, ROCK deformation, REFLECTANCE spectroscopy, MOSSBAUER spectroscopy
Abstract

We investigated a suite of impact glass‐bearing rocks using a multi‐analytical approach including visible‐near‐infrared diffuse reflectance spectroscopy, Mössbauer spectroscopy, and powder X‐ray diffraction. In order to better understand and interpret the obtained results, we built a database containing physical, chemical, and spectroscopic information on glasses and glass‐bearing materials using new results from this study and published works. We used the database to explore systematic relationships between parameters of interest and finally we applied several machine learning algorithms (support vector machine, random forests, and gradient boosting) to test the possibility to regress the oxidation state of iron from chemical and spectroscopic information. Our results show that even small amounts of mafic crystalline phases have a big influence on the spectral features of glass‐bearing rocks. Samples without mafic crystalline inclusions show the typical spectrum of glasses (two broad and shallow bands roughly centered around 1,100 and 1,900 nm) with minor variations due to bulk chemistry. We described a non‐linear relationship between average reflectance (average reflectance value between 500 and 1,000 nm), FeO + TiO2 content, grain size, and Fe3+/FeTOT. We tested the relation for the finer grain size (0–25 μm), and we qualitatively assessed how it is affected by grain size, Fe3+/FeTOT, and crystal content. Finally, we developed a machine learning pipeline to regress the Fe3+/FeTOT of glass‐bearing materials using the proposed database. Our machine learning calculations give satisfactory results (MAE: 0.0321) and additional data will enable the application of our computational strategy to remotely acquired data to extract chemical and mineralogical information of planetary surfaces. Plain Language Summary: Glasses and glass‐bearing rocks are abundant on many planetary surfaces. Glass‐bearing rocks form either as a result of rapid cooling of volcanic materials or after shock impact of (large enough) planetary bodies. Their detection from remotely acquired data remains a challenge due to the many variables affecting their spectroscopic features. More data are necessary in order to improve our knowledge of these materials. In this work, we investigated a suite of terrestrial rocks formed after impact/near surface explosion of asteroids. These rocks are characterized by a varied chemistry and different degrees of glass‐crystal ratios, making them very interesting analog planetary materials. We characterized the spectroscopic, chemical, and mineralogical features of these rocks, and we built a database containing similar information retrieved from literature data. The newly compiled database allowed us to uncover relationships between spectroscopic features and chemical/physical features of glass‐bearing materials. Given the extremely complicated physics of the shock phenomena, it is not always easy to extract useful information from the spectra of these materials. For this reason, we applied some machine learning algorithms to the newly compiled database in order to retrieve information of interest. The approach that we use is successful and suggests that when there will be more data in the database, it would be possible to use more sophisticated algorithms to retrieve information of interest from remotely acquired data. Key Points: The average reflectance in the visible‐near‐infrared spectral range is negatively correlated with FeO + TiO2 content in glassy materialsA database was built merging spectral, chemical, and physical information from several literature dataThe redox state of iron in glassy materials can be successfully regressed by a machine learning approach using spectroscopic information [ABSTRACT FROM AUTHOR]

Published
2023
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9. Reexploring the cation ordering and magnetic cation substitution effects on the elastic anisotropy of aluminum spinels.

Author

Núñez-Valdez, M., Bruschini, E., Speziale, S., Bosi, F., Fregola, R. A., D'Ippolito, V., and Andreozzi, G. B.

Subjects
MAGNESIUM alloys, SPINEL group, ELASTIC properties of metals, DENSITY functional theory, BRILLOUIN scattering
Abstract

We study the effects of cation inversion x (Mg ↔ Al, with x representing the fraction of Mg and Al exchanged) and magnetic substitution (Mn → Mg) on the elastic properties of the MgAl 2 O 4 spinel system using density functional theory and Brillouin scattering techniques. Our computations show that cation inversion decreases the molar volume of spinel and produces a stiffening of C 11 and a softening of C 12. Simulations and experiments agree within 2 %. Density functional theory also captures the qualitative effect of Mg ↔ Al on C 44 , that is, an initial softening for inversion degree at x < 0.125 and stiffening at x = 1 , with a disagreement of < 4%. The Zener anisotropy factor A decreases with increasing degree of inversion. All these trends are preserved at high pressures. The substitution of Mn for Mg produces and increases the molar volume of spinel, and it is accompanied by the softening of both C 11 and C 44 , and the stiffening of C 12 in good agreement with experimental results at ambient conditions. All these effects, which are qualitatively opposite to those of cation inversion, are enhanced at high pressures. The effect of Mn → Mg on the elastic anisotropy of spinel is, however, qualitatively similar to that of cation inversion, i.e., it causes a decrease in the Zener factor A. [ABSTRACT FROM AUTHOR]

Published
2018
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18. Evaluating the controls on the origin of tourmaline-bearing rocks in peraluminous and metaluminous systems: examples from Late-Variscan magmatism of Sardinia (Italy)

Author

Andreozzi, G. B., Bosi, F., Conte, A. M., Cuccuru, S., and Naitza, S.

Subjects
tourmaline, magmatic system, Sardinia
Abstract

In magmatic systems, intensive and compositional parameters are commonly invoked to account for tourmaline saturation in the melt. To model the frequent occurrence of tourmaline-bearing rocks associated with peraluminous intrusions, a large emphasis is typically given to Al2O3 saturation index of magmas (ASI> 1.2). However, a major role played by partial melting processes of B-bearing protoliths has been recently proposed to control the B saturation of anatectic melts. In Sardinia, a B-bearing rock series is documented by tourmaline occurrence in the late-crystallization stages of Late-Variscan intrusives related to the older magmatic peak (305-300 Ma). Conversely, intrusives related to the younger magmatic peak (290-280 Ma) are almost made up of F-bearing granites and lack in tourmaline. The controls on the origin of tourmaline were investigated by comparing mineral assemblages from Mandrolisai (central Sardinia) and Arbus (SW Sardinia) igneous massifs, both emplaced at shallow depths in the frontal zone of a nappe edifice. Mandrolisai igneous massif results as a single pulse of a granodioritic metaluminous magma, while Arbus is a composite pluton made of several pulses reaching a peraluminous character in leucogranitic rock-units (ASI < 1.16). Arbus magmas belong to a true ilmenite series while the Mandrolisai straddles the ilmenite/magnetite field series. In Mandrolisai, tourmaline occurs in layered aplite/pegmatite dikes and in thin tourmalinite veins in roof pendants of metamorphic rocks, close to the western contacts of the intrusion. In Arbus, tourmaline occurs in pegmatitic layers, in granophyric dykes and within metamorphic country rock. The inclusive crystal-chemical study of tourmaline samples from pegmatites of both plutons highlights a comparable evolution from shorlitic to foititic composition; in addition, crystals from tourmalinite veins of Mandrolisai and dispersed within the country rock of Arbus show a dravitic composition, mostly related to magma-country rock interaction. The main differences regard the Mg-richest and Al-poorest composition of Mandrolisai tourmaline, which reflect a different composition of granodioritic magma, more magnesian and less aluminous (ASI = 0.93-0.95) The whole data sets of the two plutons allow the reconstruction of the same crystallization path: T = 650-400 °C, P

Published
2019

19. Chemical and structural characterization of UICC crocidolite fibres from Koegas Mine, Northern Cape (South Africa)

Author

Pacella, A., Andreozzi, G., Nodari, L., and Ballirano, P.

Subjects
X-ray Powder Diffraction (XRPD), UICC crocidolite, surface reactivity, Asbestos, Mössbauer Spectroscopy, Rietveld method, Scanning Electron Microscopy with Energy Dispersive System (SEM-EDS), Surface reactivity, Mossbauer Spectroscopy
Abstract

In the present work we report the full structural and spectroscopic characterization of an UICC crocidolite standard sample, that is a fibrous riebeckite from Koegas Mine, Northern Cape (South Africa). The chemical composition was obtained by SEM-EDS and cation site partition was retrieved by complementing chemical, Mossbauer and X-ray powder diffraction data. Cell parameters, fractional coordinates, and site scattering for M(1), M(2), M(3), M(4) were refined using the Rietveld method. The UICC crocidolite standard sample shows the chemical formula (Na0.026Na2.000C)-Na-A-Na-B(Fe2.2122+Fe2.0413+Mg0.747)(Sigma-5.000)(T)(Si7.950Al0.022)(Sigma-7.972)O-22(o()3) (OH)(2), very close to that of the end-member riebeckite (A)square BNa2C(Fe32+Fe23+)(Sigma=5)(Si8O22o(3))-Si-T(OH)(2), the major difference being the Fe3+/Fe-tot ratio of 0.48, slightly higher than the ideal ratio of 0.40. Cation site distribution of the UICC crocidolite standard sample is: [Mg0.50Fe0.313+-Fe-1.19(2+)](Sigma=2.00) at M(1); [Mg0.10Fe1.603+Fe0.302+](Sigma=2.00) at M(2); [Mg0.15Fe0.133+Fe0.722+](Sigma=1.00) at M( 3 ). Refined cell parameters are: a=9.73516(19) angstrom, b=18.0453 (3) angstrom, c=5.32895(9) angstrom, beta =103.5159(12) degrees, V=910.23(3) angstrom(3). Quantitative Phase Analysis indicates that 93.7(3) wt% of the sample consists of crocidolite, the remaining being distributed among five different phases including magnetite and quartz.

Published
2019
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23. Affinement structural de spinelles MgFe2O4 et FeAl2O4 par tomographie de la diffraction électronique en précession

Author

Ngassa Tankeu, Y G, Jacob, Damien, Roussel, Pascal, Roskosz, Mathieu, Andreozzi, G, Unité Matériaux et Transformations - UMR 8207 (UMET), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Unité de Catalyse et de Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Ecole Centrale de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)

Subjects
[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], [CHIM.MATE]Chemical Sciences/Material chemistry, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], ComputingMilieux_MISCELLANEOUS
Abstract

National audience

Published
2017

24. Bulk spectroscopy of mineral fibres

Author

Andreozzi, G. B. and Pollastri, S.

Subjects
mineralogy, applied mineralogy, medical mineralogy, geochemistry, petrology
Published
2017

26. Asymptomatic internal carotid artery stenosis and cerebrovascular risk stratification

Author

Nicolaides, Andrew N, Kakkos, Stavros K., Kyriacou, Efthyvoulos, Griffin, Maura, Sabetai, Michael, Thomas, Dafydd J., Tegos, Thomas, Geroulakos, George, Labropoulos, Nicos, Dor, Caroline J., Morris, Tim P., Naylor, Ross, Abbott, Anne L., Adovasio, Roberto, Ziani, B., Alò, F. P., Cicilioni, C. G., Ambrosio, G., Andreev, A., Andreozzi, G. M., Verlato, F., Camporese, G., Arosio, E., Barkauskas, E., Barros D'Sa, A. A. B., Brannigan, P., Batchvarova, V., Dramov, A., Belardi, P., Novelli, Gp, Simoni, G., Bell, P., Biasi, G. M., Mingazzini, P., Bornstein, N. M., Bouchier Hayes, D., Fitzgerald, P., Cairols, M. A., Cao, P. G., Derango, P., Carboni, G. P., Geoffredo, C., Catalano, M., Chambers, B., Goetzmann, M., Dickinson, A., Clement, D., Bobelyn, M., Coccheri, S., Conti, E., Diamantopoulos, E., Andreadis, E. A., Dimakakos, P. B., Kotsis, T., Eikelboom, B., Entz, L., Ferrari Bardile, Null, Aloi, T., Salerno, M., Fernandes e. Fernandes, J., Pedro, L., Fitzgerald, D. E., O'Shaunnersy, Anne, Fletcher, J., Forconi, S., Cappeli, R., Bicchi, M., Arrigucci, S., Gallai, V., Cardaiolli, G., Geroulakos, G., Kakkos, S., Gomez Isaza, L. F., Gorgoyannis, G., Liasis, N., Graf, M., Guarini, P., Hardy, S., Harris, P., Aston, S., Iosa, G., Katsamouris, A., Giannoukas, A., Krzanowski, M., Ladurner, G., Leal Monedero, J., Lee, B. B., Liapis, C., Galanis, P., Liboni, W., Pavanelli, E., Mannarino, E., Vaudo, G., Mccollum, P., Levison, R., Micieli, G., Bosone, D., Middleton, L., Pantziaris, M., Tyllis, T., Minar, E., Willfort, A., Moggi, L., Nenci, G., Radicchia, S., Nicolaides, A., Thomas, D, Norgren, L., Ribbe, E., Novo, S., Tantillo, R., Olinic, D., Paaske, W., Pagnan, A., Pauletto, P., Pagliara, V., Pettina, G., Pratesi, C., Matticari, S., Polivka, J., Sevcik, P., Poredos, P., Blinc, A., Videcnik, V., Pujia, A., Raso, A., Rispoli, P., Conforti, M., Robinson, T., Dennis, M. S. J., Rosfors, S., Rudofsky, G., Schroeder, T., Gronholdt, M. L., Finocchi, C., Rodriguez, G., Spartera, C., Ventura, M., Scarpelli, P., Sprynger, M., Sadzot, B., Hottermans, C., Moonen, Null, Taylor, P. R., Tovar Pardo, A., Negreira, J., Vayssairat, M., Faintuch, J. M., Valaikiené, J., Walker, M. G., Wilkinson, A. R., Nicolaides, A, Kakkos, S, Kyriacou, E, Griffin, M, Sabetai, M, Thomas, D, Tegos, T, Geroulakos, G, Labropoulos, N, Dor, C, Morris, T, Naylor, R, Abbott, A, Adovasio, R, Ziani, B, Alò, F, Cicilioni, C, Ambrosio, G, Andreev, A, Andreozzi, G, Verlato, F, Camporese, G, Arosio, E, Barkauskas, E, Barros D'Sa, A, Brannigan, P, Batchvarova, V, Dramov, A, Belardi, P, Novelli, G, Simoni, G, Bell, P, Biasi, G, Mingazzini, P, Bornstein, N, Bouchier Hayes, D, Fitzgerald, P, Cairols, M, Cao, P, Derango, P, Carboni, G, Geoffredo, C, Catalano, M, Chambers, B, Goetzmann, M, Dickinson, A, Clement, D, Bobelyn, M, Coccheri, S, Conti, E, Diamantopoulos, E, Andreadis, E, Dimakakos, P, Kotsis, T, Eikelboom, B, Entz, L, Ferrari Bardileah, N, Aloi, T, Salerno, M, Fernandes, J, Pedro, L, Fitzgerald, D, O'Shaunnersy, A, Fletcher, J, Forconi, S, Cappeli, R, Bicchi, M, Arrigucci, S, Gallai, V, Cardaiolli, G, Gomez Isaza, L, Gorgoyannis, G, Liasis, N, Graf, M, Guarini, P, Hardy, S, Harris, P, Aston, S, Iosa, G, Katsamouris, A, Giannoukas, A, Krzanowski, M, Ladurner, G, Leal Monedero, J, Lee, B, Liapis, C, Galanis, P, Liboni, W, Pavanelli, E, Mannarino, E, Vaudo, G, Mccollum, P, Levison, R, Micieli, G, Bosone, D, Middleton, L, Pantziaris, M, Tyllis, T, Minar, E, Willfort, A, Moggi, L, Nenci, G, Radicchia, S, Norgren, L, Ribbe, E, Novo, S, Tantillo, R, Olinic, D, Paaske, W, Pagnan, A, Pauletto, P, Pagliara, V, Pettina, G, Pratesi, C, Matticari, S, Polivka, J, Sevcik, P, Poredos, P, Blinc, A, Videcnik, V, Pujia, A, Raso, A, Rispoli, P, Conforti, M, Robinson, T, Dennis, M, Rosfors, S, Rudofsky, G, Schroeder, T, Gronholdt, M, Finocchi, C, Rodriguez, G, Spartera, C, Ventura, M, Scarpelli, P, Sprynger, M, Sadzot, B, Hottermans, C, Moonenbp, N, Taylor, P, Tovar Pardo, A, Negreira, J, Vayssairat, M, Faintuch, J, Valaikiené, J, Walker, M, Wilkinson, A, Nicolaides, Andrew N, Kakkos, Stavros K., Kyriacou, Efthyvoulo, Griffin, Maura, Sabetai, Michael, Thomas, Dafydd J., Tegos, Thoma, Geroulakos, George, Labropoulos, Nico, Dor, Caroline J., Morris, Tim P., Naylor, Ro, Abbott, Anne L., Adovasio, Roberto, Ziani, B., Alò, F. P., Cicilioni, C. G., Ambrosio, G., Andreev, A., Andreozzi, G. M., Verlato, F., Camporese, G., Arosio, E., Barkauskas, E., Barros D'Sa, A. A. B., Brannigan, P., Batchvarova, V., Dramov, A., Belardi, P., Novelli, Gp, Simoni, G., Bell, P., Biasi, G. M., Mingazzini, P., Bornstein, N. M., Bouchier Hayes, D., Fitzgerald, P., Cairols, M. A., Cao, P. G., Derango, P., Carboni, G. P., Geoffredo, C., Catalano, M., Chambers, B., Goetzmann, M., Dickinson, A., Clement, D., Bobelyn, M., Coccheri, S., Conti, E., Diamantopoulos, E., Andreadis, E. A., Dimakakos, P. B., Kotsis, T., Eikelboom, B., Entz, L., Ferrari Bardile, Null, Aloi, T., Salerno, M., Fernandes e. Fernandes, J., Pedro, L., Fitzgerald, D. E., O'Shaunnersy, Anne, Fletcher, J., Forconi, S., Cappeli, R., Bicchi, M., Arrigucci, S., Gallai, V., Cardaiolli, G., Geroulakos, G., Kakkos, S., Gomez Isaza, L. F., Gorgoyannis, G., Liasis, N., Graf, M., Guarini, P., Hardy, S., Harris, P., Aston, S., Iosa, G., Katsamouris, A., Giannoukas, A., Krzanowski, M., Ladurner, G., Leal Monedero, J., Lee, B. B., Liapis, C., Galanis, P., Liboni, W., Pavanelli, E., Mannarino, E., Vaudo, G., Mccollum, P., Levison, R., Micieli, G., Bosone, D., Middleton, L., Pantziaris, M., Tyllis, T., Minar, E., Willfort, A., Moggi, L., Nenci, G., Radicchia, S., Nicolaides, A., Norgren, L., Ribbe, E., Novo, S., Tantillo, R., Olinic, D., Paaske, W., Pagnan, A., Pauletto, P., Pagliara, V., Pettina, G., Pratesi, C., Matticari, S., Polivka, J., Sevcik, P., Poredos, P., Blinc, A., Videcnik, V., Pujia, A., Raso, A., Rispoli, P., Conforti, M., Robinson, T., Dennis, M. S. J., Rosfors, S., Rudofsky, G., Schroeder, T., Gronholdt, M. L., Finocchi, C., Rodriguez, G., Spartera, C., Ventura, M., Scarpelli, P., Sprynger, M., Sadzot, B., Hottermans, C., Moonen, Null, Taylor, P. R., Tovar Pardo, A., Negreira, J., Vayssairat, M., Faintuch, J. M., Valaikiené, J., Walker, M. G., and Wilkinson, A. R.

Subjects
Male, Carotid Stenosi, carotid artery stenosis, Brain Ischemia, 80 and over, MED/22 - CHIRURGIA VASCOLARE, Carotid Stenosis, Cerebrovascular disease, cerebrovascular risk, Stroke, Ultrasonography, Aged, 80 and over, Middle Aged, cardiovascular system, Female, Radiology, Internal carotid artery, medicine.symptom, Cardiology and Cardiovascular Medicine, Carotid Artery, Internal, Adult, Aged, Amaurosis Fugax, Humans, ROC Curve, Risk Assessment, Surgery, Human, medicine.medical_specialty, Asymptomatic, Central nervous system disease, medicine.artery, medicine, Asymtomatic carotid stenosis, cardiovascular diseases, Risk factor, carotid surgery, Vascular disease, business.industry, Amaurosis fugax, medicine.disease, Internal, Stenosis, atherosclerosis, Carotid Artery, business
Abstract

Background: The purpose of this study was to determine the cerebrovascular risk stratification potential of baseline degree of stenosis, clinical features, and ultrasonic plaque characteristics in patients with asymptomatic internal carotid artery (ICA) stenosis. Methods: This was a prospective, multicenter, cohort study of patients undergoing medical intervention for vascular disease. Hazard ratios for ICA stenosis, clinical features, and plaque texture features associated with ipsilateral cerebrovascular or retinal ischemic (CORI) events were calculated using proportional hazards models. Results: A total of 1121 patients with 50% to 99% asymptomatic ICA stenosis in relation to the bulb (European Carotid Surgery Trial [ECST] method) were followed-up for 6 to 96 months (mean, 48). A total of 130 ipsilateral CORI events occurred. Severity of stenosis, age, systolic blood pressure, increased serum creatinine, smoking history of more than 10 pack-years, history of contralateral transient ischemic attacks (TIAs) or stroke, low grayscale median (GSM), increased plaque area, plaque types 1, 2, and 3, and the presence of discrete white areas (DWAs) without acoustic shadowing were associated with increased risk. Receiver operating characteristic (ROC) curves were constructed for predicted risk versus observed CORI events as a measure of model validity. The areas under the ROC curves for a model of stenosis alone, a model of stenosis combined with clinical features and a model of stenosis combined with clinical, and plaque features were 0.59 (95% confidence interval [CI] 0.54-0.64), 0.66 (0.62-0.72), and 0.82 (0.78-0.86), respectively. In the last model, stenosis, history of contralateral TIAs or stroke, GSM, plaque area, and DWAs were independent predictors of ipsilateral CORI events. Combinations of these could stratify patients into different levels of risk for ipsilateral CORI and stroke, with predicted risk close to observed risk. Of the 923 patients with

Published
2010
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27. Cations distribution in synthetic (MgFe2O4 and FeAl2O4) spinels by precession electron diffraction tomography

Author

Ngassa Tankeu, Yvan-Georges, Jacob, Damien, Roussel, Pascal, Roskosz, Mathieu, Andreozzi, G., Unité Matériaux et Transformations - UMR 8207 (UMET), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Unité de Catalyse et de Chimie du Solide - UMR 8181 (UCCS), and Université d'Artois (UA)-Ecole Centrale de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], [CHIM.MATE]Chemical Sciences/Material chemistry, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010403 inorganic & nuclear chemistry, 01 natural sciences, ComputingMilieux_MISCELLANEOUS, 0104 chemical sciences, 3. Good health
Abstract

International audience

Published
2016

28. Predictors and clinical significance of progression or regression of asymptomatic carotid stenosis

Author

Kakkos, Sk, Nicolaides, An, Charalambous, I, Thomas, D, Giannopoulos, A, Naylor, Ar, Geroulakos, G, Abbott, Al, Asymptomatic Carotid Stenosis, Risk of Stroke Study Group Adovasio, R, Ziani, B, Alò, F, Cicilioni, C, Ambrosio, G, Andreev, A, Andreozzi, G, Verlato, F, Camporese, G, Arosio, E, Barkauskas, E, D'Sa, A, Brannigan, P, Batchvarova, V, Dramov, A, Belardi, P, Novelli, G, Simoni, G, Bell, P, Biasi, G, Mingazzini, P, Bornstein, N, Bouchier Hayes, D, Fitzgerald, P, Cairols, M, Cao, P, Derango, P, Carboni, G, Geoffredo, C, Catalano, M, Chambers, B, Goetzmann, M, Dickinson, A, Clement, D, Bobelyn, M, Coccheri, S, Conti, E, Diamantopoulos, E, Andreadis, E, Dimakakos, P, Kotsis, T, Eikelboom, B, Entz, L, Ferrari Bardile, A, Aloi, T, Salerno, M, Fernandes J, Fernandes e., Pedro, L, Fitzgerald, D, O'Shaughnessy, A, Fletcher, J, Forconi, S, Cappeli, R, Bicchi, M, Arrigucci, S, Gallai, V, Cardaiolli, G, Kakkos, S, Gomez Isaza, L, Gorgoyannis, G, Liasis, N, Graf, M, Guarini, P, Hardy, S, Harris, P, Aston, S, Iosa, G, Katsamouris, A, Giannoukas, A, Krzanowski, M, Ladurner, G, Leal Monedero, J, Lee, B, Liapis, C, Galanis, P, Liboni, W, Pavanelli, E, Mannarino, E, Vaudo, G, Mccollum, P, Levison, R, Micieli, G, Bosone, D, Middleton, L, Pantziaris, M, Tyllis, T, Minar, E, Willfort, A, Moggi, L, Nenci, G, Radicchia, S, Nicolaides, A, Norgren, L, Ribbe, E, Novo, S, Tantillo, R, Olinic, D, Paaske, W, Pagnan, A, Pauletto, P, Pagliara, V, Pettina, G, Pratesi, C, Matticari, S, Polivka, J, Sevcik, P, Poredos, P, Blinc, A, Videcnik, V, Pujia, A, Raso, A, Rispoli, Pietro, Conforti, M, Robinson, T, Dennis, M, Rosfors, S, Rudofsky, G, Schroeder, T, Gronholdt, M, Finocchi, C, Rodriguez, G, Spartera, C, Ventura, M, Scarpelli, P, Sprynger, M, Sadzot, B, Hottermans, C, Moonen, M, Taylor, P, Tovar Pardo, A, Negreira, J, Vayssairat, M, Faintuch, J, Valaikiené, J, Walker, M, Wilkinson, A. R., Kakkos, Stavros K., Nicolaides, Andrew N., Charalambous, Ioanna, Thomas, Dafydd, Giannopoulos, Argyrio, Naylor, A. Ro, Geroulakos, George, Abbott, Anne L., Adovasio, Roberto, Ziani, B., Alò, F. P., Cicilioni, C. G., Ambrosio, G., Andreev, A., Andreozzi, G. M., Verlato, F., Camporese, G., Arosio, E., Barkauskas, E., Barros D'Sa, A. A. B., Brannigan, P., Batchvarova, V., Dramov, A., Belardi, P., Novelli, G. P., Simoni, G., Bell, P., Biasi, G. M., Mingazzini, P., Bornstein, N. M., Bouchier Hayes, D., Fitzgerald, P., Cairols, M. A., Cao, P. G., Derango, P., Carboni, G. P., Geoffredo, C., Catalano, M., Chambers, B., Goetzmann, M., Dickinson, A., Clement, D., Bobelyn, M., Coccheri, S., Conti, E., Diamantopoulos, E., Andreadis, E. A., Dimakakos, P. B., Kotsis, T., Eikelboom, B., Entz, L., Ferrari Bardile, A., Aloi, T., Salerno, M., Fernandes E. Fernandes, J., Pedro, L., Fitzgerald, D. E., O'Shaughnessy, A. M., Fletcher, J., Forconi, S., Cappeli, R., Bicchi, M., Arrigucci, S., Gallai, V., Cardaiolli, G., Gomez Isaza, L. F., Gorgoyannis, G., Liasis, N., Graf, M., Guarini, P., Hardy, S., Harris, P., Aston, S., Iosa, G., Katsamouris, A., Giannoukas, A., Krzanowski, M., Ladurner, G., Leal Monedero, J., Lee, B. B., Liapis, C., Galanis, P., Liboni, W., Pavanelli, E., Mannarino, E., Vaudo, G., Mccollum, P., Levison, R., Micieli, G., Bosone, D., Middleton, L., Pantziaris, M., Tyllis, T., Minar, E., Willfort, A., Moggi, L., Nenci, G., Radicchia, S., Norgren, L., Ribbe, E., Novo, S., Tantillo, R., Olinic, D., Paaske, W., Pagnan, A., Pauletto, P., Pagliara, V., Pettina, G., Pratesi, C., Matticari, S., Polivka, J., Sevcik, P., Poredos, P., Blinc, A., Videcnik, V., Pujia, A., Raso, A., Rispoli, P., Conforti, M., Robinson, T., Dennis, M. S. J., Rosfors, S., Rudofsky, G., Schroeder, T., Gronholdt, M. L., Finocchi, C., Rodriguez, G., Spartera, C., Ventura, M., Scarpelli, P., Sprynger, M., Sadzot, B., Hottermans, C., Moonen, M., Taylor, P. R., Tovar Pardo, A., Negreira, J., Vayssairat, M., Faintuch, J. M., Valaikiené, J., Walker, M. G., and Wilkinson, A. R.

Subjects
Male, Time Factors, Cost effectiveness, medicine.medical_treatment, Carotid Stenosi, Predictive Value of Test, Kaplan-Meier Estimate, Carotid endarterectomy, Retinal Disease, Risk Factors, 80 and over, Carotid Stenosis, Plaque, Atherosclerotic, Ultrasonography, Aged, 80 and over, Ultrasonography, Doppler, Duplex, Incidence, Remission Induction, Doppler, Middle Aged, Prognosis, Plaque, Atherosclerotic, Duplex, Europe, Stroke, Predictive value of tests, Disease Progression, Cardiology, Female, medicine.symptom, Cardiology and Cardiovascular Medicine, Carotid Artery, Internal, Human, Adult, medicine.medical_specialty, Time Factor, Victoria, Prognosi, Asymptomatic, Retinal Diseases, Predictive Value of Tests, Internal medicine, medicine, Humans, Clinical significance, Aged, Asymptomatic Disease, business.industry, Risk Factor, medicine.disease, Internal, Confidence interval, Surgery, Stenosis, Asymptomatic Diseases, Relative risk, asymptomatic carotid artery stenosis, Carotid Artery, business
Abstract

OBJECTIVE: To determine baseline clinical and ultrasonographic plaque factors predictive of progression or regression of asymptomatic carotid stenosis and the predictive value of changes in stenosis severity on risk of first ipsilateral cerebral or retinal ischemic events (including stroke).METHODS: A total of 1121 patients with asymptomatic carotid stenosis of 50% to 99% in relation to the bulb diameter (European Carotid Surgery Trial [ECST] method) underwent six monthly clinical assessments and carotid duplexes for up to 8 years (mean follow-up, 4 years). Progression or regression was considered present if there was a change of at least one grade higher or lower, respectively, persisting for at least two consecutive examinations.RESULTS: Regression occurred in 43 (3.8%), no change in 856 (76.4%), and progression in 222 (19.8%) patients. Younger age, high grades of stenosis, absence of discrete white areas in the plaque, and taking lipid lowering therapy were independent baseline predictors of increased incidence of regression. High serum creatinine, male gender, not taking lipid lowering therapy, low grades of stenosis, and increased plaque area were independent baseline predictors of progression. One hundred and thirty first ipsilateral cerebral or retinal ischemic events, including 59 strokes, occurred. Forty (67.8%) of the strokes occurred in patients whose stenosis was unchanged, 19 (32.2%) in those with progression, and zero in those with regression. For the entire cohort, the 8-year cumulative ipsilateral cerebral ischemic stroke rate was zero in patients with regression, 9% if the stenosis was unchanged, and 16% if there was progression (average annual stroke rates of 0%, 1.1%, and 2.0%, respectively; log-rank, P = .05; relative risk in patients with progression, 1.92; 95% confidence interval, 1.14-3.25). For patients with baseline stenosis 70% to 99% in relation to the distal internal carotid (North American Symptomatic Carotid Endarterectomy Trial [NASCET] method), in the absence of progression (n = 349), the 8-year cumulative ipsilateral cerebral ischemic stroke rate was 12%. In the presence of progression (n = 77), it was 21% (average annual stroke rates of 1.5% and 2.6%, respectively; log-rank, P = .34). Only nine (30%) of the 30 strokes occurred in the progression group.CONCLUSIONS: Progressive asymptomatic carotid stenosis identified a subgroup with about twice the risk of ipsilateral stroke compared with those without progression. However, the clinical value of screening for progression simply for selecting patients for carotid procedures is limited because of the low frequency of progression and its relatively low associated stroke rate. The cost effectiveness of screening for change in stenosis severity to better direct current optimal medical treatment needs testing.

Published
2014
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30. EFFECTS OF DEFIBROTIDE IN PATIENTS WITH CHRONIC DEEP INSUFFICIENCY. THE PROVEDIS STUDY

Author

COCCHERI S, ANDREOZZI G. M, DADDATO M, GENSINI GF, NOVO, Salvatore, COCCHERI S, ANDREOZZI G M, DADDATO M, GENSINI GF, and NOVO S

Subjects
Male, fibrinolytic agent, Ultrasonography, Doppler, Middle Aged, Bandages, venous insufficiency, therapy, Polydeoxyribonucleotides, Double-Blind Method, Fibrinolytic Agents, Chronic Disease, Humans, Female, Vascular Diseases, venous thrombosis, Ankle, Aged
Abstract

Aim. In the ­present study the ­effect of defi­bro­tide, an anti­throm­bot­ic and prof­i­brin­o­lyt­ic agent, was inves­ti­gat­ed in ­patients with chron­ic ­venous insuf­fi­cien­cy (CVI) due to deep vein obstruc­tion and/or ­reflux (chron­ic deep vein insuf­fi­cien­cy, CDVI). Meth­ods. The study was a mul­ti­cen­ter, ran­dom­ized, dou­ble blind pla­ce­bo con­trolled trial in which only ­patients with CDVI con­firmed by ultra­sound were ­enrolled. All ­patients were treat­ed with ade­quate elas­tic com­pres­sion and ran­dom­ized to ­receive ­either oral defi­bro­tide (800 mg/die) or match­ing pla­ce­bo for 1 year. ­Patients with ­active or pre­vi­ous leg ulcer were exclud­ed. ­Results. A total of 288 ­patients were ran­dom­ized and 159 com­plet­ed the study. At base­line ultra­sound inves­ti­ga­tion, obstruc­tive chang­es were found in 2/3 of all ­patients thus ascer­tain­ing a post-throm­bot­ic syn­drome (PTS). The pri­mary end­point, ankle cir­cum­pher­ence, was sig­nif­i­cant­ly ­reduced under defi­bro­tide from day 120 through­out 360. ­Scores for pain and edema were ­improved. The num­ber of epi­sodes of super­fi­cial throm­boph­le­bitis and deep vein throm­bo­sis was sig­nif­i­cant­ly lower under defi­bro­tide (n=2) than under pla­ce­bo (n=10). The major­ity of these ­events ­occurred in the sub­set of ­patients with doc­u­ment­ed PTS. Con­clu­sion. Treat­ment with defibro­tide in addi­tion to elas­tic com­pres­sion in ­patients with objec­tive­ly ­assessed CDVI, most­ly due to PTS, result­ed in clin­i­cal ben­e­fits and pre­vent­ed throm­bot­ic com­pli­ca­tions harm­ful to the limb conditions

Published
2004

31. The size of juxtaluminal hypoechoic area in ultrasound images of asymptomatic carotid plaques predicts the occurrence of stroke

Author

Kakkos, Sk, Griffin, Mb, Nicolaides, An, Kyriacou, E, Sabetai, Mm, Tegos, T, Makris, Gc, Thomas, Dj, Geroulakos, G, Asymptomatic Carotid Stenosis, Risk of Stroke Study Group, Adovasio, R, Ziani, B, Alò, F, Cicilioni, C, Ambrosio, G, Andreev, A, Andreozzi, G, Verlato, F, Camporese, G, Arosio, E, Barkauskas, E, Barros, A, Brannigan, P, Batchvarova, V, Dramov, A, Belardi, P, Novelli, G, Simoni, G, Bell, P, Biasi, G, Mingazzini, P, Bornstein, N, Bouchier Hayes, D, Fitzgerald, P, Cairols, M, Cao, P, Derango, P, Carboni, G, Geoffredo, C, Catalano, M, Chambers, B, Goetzmann, M, Dickinson, A, Clement, D, Bobelyn, M, Coccheri, S, Conti, E, Diamantopoulos, E, Andreadis, E, Dimakakos, P, Kotsis, T, Eikelboom, B, Entz, L, Ferrari Bardile, A, Aloi, T, Salerno, M, Fernandes, J, Pedro, L, Fitzgerald, D, O'Shaughnessy, A, Fletcher, J, Forconi, S, Cappeli, R, Bicchi, M, Arrigucci, S, Gallai, V, Cardaiolli, G, Kakkos, S, Gomez Isaza, L, Gorgoyannis, G, Liasis, N, Graf, M, Guarini, P, Hardy, S, Harris, P, Aston, S, Iosa, G, Katsamouris, A, Giannoukas, A, Krzanowski, M, Ladurner, G, Leal Monedero, J, Lee, B, Liapis, C, Galanis, P, Liboni, W, Pavanelli, E, Mannarino, E, Vaudo, G, Mccollum, P, Levison, R, Micieli, G, Bosone, D, Middleton, L, Pantziaris, M, Tyllis, T, Minar, E, Willfort, A, Moggi, L, Nenci, G, Radicchia, S, Nicolaides, A, Thomas, D, Norgren, L, Ribbe, E, Novo, S, Tantillo, R, Olinic, D, Paaske, W, Pagnan, A, Pauletto, P, Pagliara, V, Pettina, G, Pratesi, C, Matticari, S, Polivka, J, Sevcik, P, Poredos, P, Blinc, A, Videcnik, V, Pujia, A, Raso, A, Rispoli, Pietro, Conforti, M, Robinson, T, Dennis, M, Rosfors, S, Rudofsky, G, Schroeder, T, Gronholdt, M, Finocchi, C, Rodriguez, G, Spartera, C, Ventura, M, Scarpelli, P, Sprynger, M, Sadzot, B, Hottermans, C, Moonen, M, Taylor, P, Tovar Pardo, A, Negreira, J, Vayssairat, M, Faintuch, J, Valaikiené, J, Walker, M, Wilkinson, R., Stavros K., Kakko, Maura B., Griffin, Andrew N., Nicolaide, Efthyvoulos, Kyriacou, Michael M., Sabetai, Thomas, Tego, Gregory C., Makri, Dafydd J., Thoma, George, Geroulako, Asymptomatic Carotid, Stenosi, Risk of Stroke Study, Group, Adovasio, Roberto, Kakkos, SK, Griffin, MB, Nicolaides, AN, Kyriacou, E, Sabetai, MM, Tegos, T, Makris, GC, Thomas, DJ, Geroulakos, G, and Novo, s

Subjects
Asymptomatic carotid plaque, Male, Time Factors, medicine.medical_treatment, Carotid endarterectomy, Kaplan-Meier Estimate, Severity of Illness Index, asymptomatic carotid artery stenosis, hypoecoic area, Stroke, Risk Factors, Carotid Stenosis, Ultrasonography, Doppler, Color, Prospective cohort study, Aged, 80 and over, Neovascularization, Pathologic, Middle Aged, Prognosis, Plaque, Atherosclerotic, Europe, Ischemic Attack, Transient, Predictive value of tests, Female, Radiology, medicine.symptom, juxtaluminal hypoechoic area, ultrasound images, asymptomatic carotid plaques, stroke, Cardiology and Cardiovascular Medicine, Carotid Artery, Internal, Adult, medicine.medical_specialty, Asymptomatic, Risk Assessment, Brain ischemia, Echography, Predictive Value of Tests, asymptomatic carotid artery stenosi, medicine, Humans, cardiovascular diseases, Aged, Proportional Hazards Models, business.industry, Proportional hazards model, medicine.disease, Acoustic shadow, Settore MED/11 - Malattie Dell'Apparato Cardiovascolare, Stenosis, ROC Curve, Asymptomatic Diseases, Linear Models, Surgery, business, Follow-Up Studies
Abstract

OBJECTIVE: To test the hypothesis that the size of a juxtaluminal black (hypoechoic) area (JBA) in ultrasound images of asymptomatic carotid artery plaques predicts future ipsilateral ischemic stroke. METHODS: A JBA was defined as an area of pixels with a grayscale value 10 mm(2) (P < .001). In a Cox model with ipsilateral ischemic events (amaurosis fugax, transient ischemic attack [TIA], or stroke) as the dependent variable, the JBA (8 mm(2)) was still significant after adjusting for other plaque features known to be associated with increased risk, including stenosis, grayscale median, presence of discrete white areas without acoustic shadowing indicating neovascularization, plaque area, and history of contralateral TIA or stroke. Plaque area and grayscale median were not significant. Using the significant variables (stenosis, discrete white areas without acoustic shadowing, JBA, and history of contralateral TIA or stroke), this model predicted the annual risk of stroke for each patient (range, 0.1%-10.0%). The average annual stroke risk was

Published
2013
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32. Environmental and biological monitoring of polycyclic aromatic hydrocarbon levels in outdoor workers exposed to urban stressor

Author

Sancini, A., Tomei, F., Montuori, L., Caciari, T., Andrè, J. C., Rinaldi, G., Andreozzi, G., Sinibaldi, F., Schifano, M. P., Tomei, G., Simone De Sio, Capozzella, A., and Ciarrocca, M.

Subjects
Adult, Male, Air Pollutants, Pyrenes, Italy, Occupational Exposure, Urban Health, Humans, Transportation, Middle Aged, Polycyclic Aromatic Hydrocarbons, Police, Environmental Monitoring
Abstract

Purpose of this study is to evaluate and to compare the excretion of urinary 1-hydroxypyrene (1-OHPu) in traffic policemen (TP) and drivers (D) of a large Italian city and to evaluate the existence and the degree of correlation between airborne exposure to 15 different polycyclic aromatic hydrocarbons (PAHs) and 1-OHPu levels in the examined population.192 male workers, 115 TP and 77 D, were monitored for 1-HOPu. A subgroup of non-smoking workers (subgroup B: 59 TP and 15 D) was also examined and 15 environmental PAHs was monitored through the personal samplings for the measurement of the particulate phase.The 1-OHPu levels and the values of personal airborne exposure to PAHs were significantly higher among non-smoking TP than among non-smoking D (p0.05). In subgroup B the levels of environmental exposure to all the 15 PAHs measured in TP and only 6 of 15 PAHs measured in D were significantly correlated with the values of 1-OHPu (p0.05).Our results suggest that the use of 1-OHPu as an indicator of exposure to PAHs is reliable also for what concerns the study of the low-dose work-related exposure in urban outdoor workers.

Published
2012

33. Shift work and night work and mental health

Author

Sancini, Angela, Ciarrocca, Manuela, Capozzella, Assuntina, Corbosiero, P, Fiaschetti, Maria, Caciari, T, Cetica, Carlotta, Scimitto, Lara, Ponticiello, Bg, Tasciotti, Zaira, Schifano, MARIA PIA, Andreozzi, G, Tomei, Francesco, and Tomei, Gianfranco

Subjects
Circadian rhythm, Depression, Anxiety
Published
2012

37. Assumed correlation between VIP and MT in the kidney of Carassius auratus L. subjected to chronic cadmium intoxication

Author

BATTAGLINI P., DE GIROLAMO, PAOLO, ARCAMONE, NADIA, ANDREOZZI G., FERRARA L., SOPPELSA, OTTAVIO, GARGIULO G., ESPOSITO, VINCENZO, Battaglini, Pietro, DE GIROLAMO, Paolo, Arcamone, Nadia, Esposito, Vincenzo, Andreozzi, Giuliana, Ferrara, Luciano, Soppelsa, Ottavio, Gargiulo, Giuliana, Battaglini, P., Andreozzi, G., Ferrara, L., and Gargiulo, G.

Subjects
kidney, Vasoactive Intestinal Peptide (Vip), Carassius auratu, Metallothionein
Published
1994

38. Oxidative enzymes and cadmium uptake in the kidney of Carassius auratus L. subjected to experimental chronic intoxication

Author

GARGIULO G., ARCAMONE, NADIA, DE GIROLAMO, PAOLO, ANDREOZZI G., ANTONUCCI R., FERRARA L., BATTAGLINI P., ESPOSITO, VINCENZO, Gargiulo, Giuliana, DE GIROLAMO, Paolo, Arcamone, Nadia, Andreozzi, Giuliana, Antonucci, Rosanna, Esposito, Vincenzo, Ferrara, Luciano, Battaglini, Pietro, Gargiulo, G., Andreozzi, G., Antonucci, R., Ferrara, L., and Battaglini, P.

Subjects
kidney, cadmium uptake, Carassius auratus, Oxidative enzyme
Published
1994

40. Iloprost, stable analogue of the prostacyclin, is able to improve the tissue resistance to ischaemia

Author

Andreozzi, G. M., luigi Di Pino, Li Pira, M., Butto, G., Martini, R., and Signorelli, S.

Subjects
Oxygen, Ischemia, Humans, Arterial Occlusive Diseases, Iloprost, Carbon Dioxide
Abstract

On 10 patients, suffering from peripheral arterial disease, with critical limb ischaemia, the CO2 production during ischaemia has been evaluated at 1st and at 28th day of treatment with iloprost. The study demonstrated that the drug is able to improve the tissue resistance to ischaemia, with a significant (p0.05) reduction of the CO2 production. The authors underline that this study is one of the first confirmations, in vivo and on the man, of the previous experimental findings, made in isolated arterial tissue.

Published
1994

41. Iron speciation in minerals and glasses probed by $$\hbox{M}_{2/3}$$ -edge X-ray Raman scattering spectroscopy.

Author

Nyrow, A., Sternemann, C., Wilke, M., Gordon, R., Mende, K., Yavaş, H., Simonelli, L., Hiraoka, N., Sahle, Ch., Huotari, S., Andreozzi, G., Woodland, A., Tolan, M., and Tse, J.

Subjects
RAMAN scattering, SPECTRUM analysis, OXIDATION states, X-ray spectroscopy, ELECTRONIC structure, IRON, COORDINATE covalent bond
Abstract

We present a spectroscopic study of the iron $$\hbox{M}_{2/3}$$ -edge for several minerals and compounds to reveal information about the oxidation state and the local coordination of iron. We describe a novel approach to probe the iron $$\hbox{M}_{2/3}$$ -edge bulk sensitively using X-ray Raman scattering. Significant changes in the onset and shape of the Fe $$\hbox{M}_{2/3}$$ -edge were observed on ferrous and ferric model compounds with Fe in octahedral and tetrahedral coordination. Simulation of the spectra is possible using an atomic multiplet code, which potentially allows determination of, e.g., crystal-field parameters in a quantitative manner. A protocol is discussed for determination of the Fe oxidation state in compounds by linear combination of spectra of ferric and ferrous end members. The presented results demonstrate the capabilities of Fe $$\hbox{M}_{2/3}$$ -edge spectroscopy by X-ray Raman scattering to extract information on the ratio of trivalent to total iron $$\hbox{Fe}^{3+}/\sum \hbox{Fe}$$ and local coordination. As X-ray Raman scattering is performed with hard X-rays, this approach is suitable for in situ experiments at high pressure and temperature. It thus may provide indispensable information on oxidation state, electronic structure and local structure of materials that are important for physical and chemical processes of the deep Earth. [ABSTRACT FROM AUTHOR]

Published
2014
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43. Crystallographic and spectroscopic characterization of a natural Zn-rich spinel approaching the endmember gahnite (ZnAl2O4) composition.

Author

D'IPPOLITO, V., ANDREOZZI, G. B., BOSI, F., HÅLENIUS, U., MANTOVANI, L., BERSANI, D., and FREGOLA, R. A.

Subjects
*ZINC alloys, *GEMS & precious stones, *MINERALS, *CRYSTALS, *OXIDE synthesis
Abstract

The crystal chemistry of a natural, gem-quality, blue-grey Zn-rich spinel crystal from Jemaa, Kaduna State, Nigeria, was studied using electron microprobe, single-crystal X-ray diffraction, optical absorption and Raman spectroscopies. The composition of the crystal approaches the gahnite endmember (ZnAl2O4), ∼94 mol.%, with the remainder being dominated by a hercynite component (FeAl2O4). The unit-cell dimension is 8.0850(3) Å and the tetrahedral and octahedral bond distances are determined as T-O 1.9485(6) Å and M-O 1.9137(3) Å . Crystal chemical analysis resulted in the empirical structural formula T(Zn0.94Fe2+0.03Al0.03)M(Al1.96Fe2+0.03Fe3+0.0.1)O4, which shows Zn and Al almost fully ordered in the tetrahedrally and octahedrally coordinated T and M sites, respectively. Raman spectra obtained using the excitation of the blue 473.1 nm line of a Nd:YAG laser display three of the five Raman-active modes predicted for the general oxide spinel group of minerals. These are the Eg mode at 420.6 cm-1 and the T2g modes at 510 cm-1 and 661 cm-1, due to vibrations in the AlO6 octahedra. Optical absorption spectra recorded in the UV/VIS-NIR-MIR range 2000-29000 cm-1 show a dominant absorption band at ∼5000 cm-1 which is caused by spin-allowed electronic d-d transitions in Fe2+ located at the T sites. The blue-grey hue exhibited by the sample is mainly due to spin-forbidden electronic transitions in TFe2+ and to MFe2+ → MFe3+ intervalence charge transfer, and the poor saturation of the colour is due to the small concentration of Fe2+ and Fe3+. [ABSTRACT FROM AUTHOR]

Published
2013
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44. Ogre retrotransposons in Lathyrus species.

Author

Ceccarelli, M., Sarri, V., Polizzi, E., Andreozzi, G., and Cionini, P.G.

Subjects
RETROTRANSPOSONS, DNA, NUCLEOTIDE sequence, PEAS, LATHYRUS
Abstract

A repeated DNA element (pLsat10) 225 bp in length, whose nucleotide sequence was partly identical to that of the PBS of Ogre retrotransposons in Pisum sativum and in part 78.3% similar to that of the adjoining portion of the 5′ LTR of these retroelements, was isolated from a partial genomic library of Lathyrus sativus. By using this DNA sequence in dot-blot and Southern blot hybridizations, Ogre retrotransposons were traced and studied in four Lathyrus species (L. latifolius, L. odoratus, L. sativus, and L. sylvestris). The copy number per ng of DNA of pLsat-related sequences in L. sativus turned out to be 1.5×107, and an upper limit estimate of the proportion of the genome made up by Ogre may be 10–16%. The results of Southern blot hybridization of pLsat10 to genomic DNAs indicated the occurrence, in each Lathyrus genome, of distinct subfamilies of Ogre and suggested a higher activity of these retrotransposons in annual than in perennial species. Fluorescent in situ hybridization of pLsat10 showed Ogre to be widely dispersed in all chromosomes, but poorly represented or absent in heterochromatic chromosome regions. [ABSTRACT FROM AUTHOR]

Published
2013
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45. RESPIRATORY PARAMETERS IN TRAFFIC POLICEMEN EXPOSED TO URBAN POLLUTION.

Author

Sancini, A., Caciari, T., Andreozzi, G., Scimitto, L., Schifano, M. P., Di Giorgio, V., Samperi, I., Ferrante, E., Fiaschetti, M., Tomei, G., and Tomei, F.

Subjects
URBAN pollution, VITAL capacity (Respiration), TRAFFIC police, SPIROMETRY, POLICE, URBAN transportation, RESPIRATORY measurements
Abstract

Studies in scientific literature have proved that urban pollution affects the respiratory system. The aim of our study is to assess the effects that different time of exposure to urban pollution can cause on respiratory function in municipal traffic policemen. The research was carried out on a sample of 120 traffic police officers of both sexes divided into two groups, group A with work service between land 10 years and group B with more than 10 years of service. All subjects included in the study were tested for respiratory functions by a spirometer test. Statistical analysis showed a significant difference between group A and group B (p<0.005) in some spirometric parameters, such as Forced Expiratory Volume in one second (FEV1) and Forced Vital Capacity (FVC). The study suggests that longer occupational exposure to urban pollutants increases the risk of modifications of respiratory function. [ABSTRACT FROM AUTHOR]

Published
2010
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46. Characterization, Evolution and Chromosomal Distribution of Two Satellite DNA Sequence Families in Lathyrus species.

Author

Ceccarelli, M., Sarri, V., Polizzi, E., Andreozzi, G., and Cionini, P. G.

Subjects
SATELLITE DNA, NUCLEOTIDE sequence, LATHYRUS, PLANT species, PLANT evolution, PLANT genetics
Abstract

DNA clones containing highly repetitive DNA sequences were selected from partial libraries of Lathyrus sativus and L. sylvestris. Two satellite DNA sequence families were isolated from the genome of the former species. A first family was made up of repeats that varied in length from 54–56 bp, and shared 51.7–94.8% nucleotide sequence similarity. The repeats of the second sequence family were 52–62 bp in length, and shared a 58.5–78.5% nucleotide sequence similarity. All the repeat units contained in a clone from L. sylvestris were 41 bp in length and showed an almost perfect structural conservation (95.1–100% nucleotide sequence similarity). The evolution of the first sequence family from L. sativus and of that isolated from L. sylvestris was studied by dot-blot hybridization to the genomic DNA of these species and 3 other Lathyrus species, L. clymenum, L. latifolius and L. odoratus. The former repeats were found to be species-specific and their redundancy was calculated to be 2.9 × 107. The satellite DNA sequence isolated from L. sylvestris was present also in L.latifolius, with a redundancy of 1.4 × 107 and 1.1 × 107, respectively. Fluorescent in situ hybridization (FISH) was used to investigate the chromosomal distribution of the two sequence families and of 45S and 5S ribosomal genes. The species-specific sequences of L. sativus were located around the centromere of chromosome pair IV, where they occupied a very broad region, and, in a much smaller amount, close to the centromere in the short arm of pair II. Sequences related to the repeat units isolated from L. sylvestris were found, both in this species and L. latifolius, in all of the chromosome pairs at terminal and interstitial regions, where they co-localize with the vast majority of DAPI bands. The pattern of distribution of the satellite DNA sequences investigated, together with that of DAPI bands and ribosomal DNA, allowed each chromosome pair of the 3 complements studied to be identified unambiguously. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Published
2010
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47. HF2EPR spectroscopy of Fe(III) impurities in a blue hercynite-based pigment

Author

Di Benedetto, F., Andreozzi, G., Baldi, G., Barzanti, A., Bernardini, G.P., Faso, V., Pardi, L.A., and Romanelli, M.

Subjects
*IRON, *CHARGE transfer, *ELECTRON paramagnetic resonance, *MOSSBAUER spectroscopy, *CRYSTAL field theory
Abstract

Abstract: The nature and the behavior of a paramagnetic Fe(III) impurity, occurring in a new charge-transfer hercynite-based blue pigment and determined through conventional electron paramagnetic resonance (EPR) and Mössbauer spectroscopy, was investigated and ascertained through high-field high-frequency EPR (HF2EPR) spectroscopy. The blue hercynite-based pigment is biphasic, containing both hercynite and corundum. The HF2EPR spectral features, together with their temperature dependence allowed to assess the intensity and the symmetry of the Fe(III) crystal field interactions. Numerical simulations were used to determine the relevant hamiltonian parameters. The final attribution of Fe(III) to the octahedral sites in corundum was achieved. The presence of corundum was found to remove ferric iron, eventually formed during the synthesis, from hercynite. The dilution of Fe(III) in the Al2O3 phase results in a quenching of its coloring effects. As a consequence, corundum acts as a buffer during the synthesis, stabilizing the pigment chromatic yield. [Copyright &y& Elsevier]

Published
2006
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48. Crystal chemical and 57Fe Mössbauer study of chromite from the Nuggihalli schist belt (India).

Author

Lenaz, D., Andreozzi, G. B., Mitra, S., Bidyananda, M., and Princivalle, F.

Subjects
*SERPENTINE, *SILICATE minerals, *OXIDATION, *CHROMITE, *ELECTRONS, *MAGNESIUM, *ALUMINUM
Abstract

Summary In the Nuggihalli schist belt (India), chromite bodies were affected by intense serpentinization followed by weathering. In spite of the strong oxidation of the chromite grains, some unaltered cores were preserved, and they were characterised using electron probe microanalysis, single-crystal X-ray diffraction and low temperature 57Fe Mössbauer spectroscopy. Results of such investigations revealed that chromite cores from the Nuggihalli schist belt are effectively not oxidised, and their study revealed that chromite was not affected by greenschist-facies metamorphism. The apparently highly ordered cation distribution of the chromites, which would suggest low equilibration temperature, is just caused by the very high Cr contents, which prevent Mg–Al exchange between T and M sites. Using Fabries (1979) geothermometer a temperature of about 1180 °C was retrieved (Mitra and Bidyananda, 2003), which therefore corresponds to the quenched-in igneous equilibrium. [ABSTRACT FROM AUTHOR]

Published
2004
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49. Influence of cation distribution on the optical absorption spectra of Fe3+-bearing spinel s.s.–hercynite crystals: evidence for electron transitions in VIFe2+–VIFe3+ clusters.

Author

Hålenius, U., Skogby, H., and Andreozzi, G. B.

Abstract

Flux-grown Fe3+-bearing spinel s.s.–hercynite solid-solution crystals, (Mg 1-yFe2+ y)Al2O4 (0 < y≤ 1), have been investigated by means of electron microprobe technique and Mössbauer and electronic spectroscopy. Obtained results show that different electronic processes cause intense optical absorption bands in the near-infrared spectral region. In addition to an electronic d– d transition in single-ion IVFe2+, observed at 5200 cm−1, intense and broad bands at 9500 and 14 500 cm−1 are assigned to exchange-coupled pair (ECP) and intervalence charge-transfer (IVCT) transitions in VI Fe 2+ VIFe3+clusters, respectively. The net linear extinction coefficients of these bands ( α) were calibrated against Fe2+ and Fe3+ concentrations and site distributions previously defined by combined microchemical, Mössbauer, and XRD structural refinement data. The following expressions were obtained: where α is measured in cm−1 and concentrations are expressed in mol l−1. The present results show that optical absorption spectroscopy may be used as a probe to obtain high spatial resolution (∅∼ 10 μm) information on Fe2+ ordering as well as on Fe3+ concentrations in minerals belonging to the spinel group. [ABSTRACT FROM AUTHOR]

Published
2002
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50. Spectroscopic active IVFe3+–VIFe3+ clusters in spinel–magnesioferrite solid solution crystals: a potential monitor for ordering in oxide spinels.

Author

Andreozzi, G. B., Hålenius, U., and Skogby, H.

Abstract

Optical absorption spectra (OAS) of synthetic single crystals of the solid solution spinel sensu stricto (s.s.)–magnesioferrite, Mg(Fe3+Al1 − y)2O4 (0 < y ≤ 0.3), have been measured between 12 500 and 28 500 cm−1. Chemical composition and Fe3+ site distribution have been measured by electron microprobe and Mössbauer spectroscopy, respectively. Ferric iron is ordered to the tetrahedral site for samples with small magnesioferrite component, and this ordering is shown to increase with magnesioferrite component. The optical absorption spectra show a strong increase in band intensities with Fe3+→Al substitution. Prominent and relatively sharp absorption bands are observed at 25 300 and 21 300 cm−1, while less intense bands occur at 22 350, 18 900, 17 900 and 15 100 cm−1. On the basis of band energies, band intensities and the compositional effect on band intensity, as well as structural considerations, we assign the observed bands to electronic transitions in IVFe3+–VIFe3+clusters. A linear relationship ( R2= 0.99) between the αnet value of the absorption band at 21 300 cm−1 and [IVFe3+] · [VIFe3+] concentration product has been defined: αnet=2.2 + 15.8 [IVFe3+] · [VIFe3+]. Some of the samples have been heat-treated between 700 and 1000 °C to investigate the relation between Fe3+ ordering and absorption spectra. Increase of cation disorder with temperature is observed, which corresponds to a 4% reduction in the number of active clusters. Due to the high spatial resolution (∅ ∼ 10 μm), the OAS technique may be used as a microprobe for determination of Fe3+ concentration or site partitioning. Potential applications of the technique include analysis of small crystals and of samples showing zonation with respect to total Fe3+ and/or ordering. [ABSTRACT FROM AUTHOR]

Published
2001
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